Tube amps and heat

[Cory rich40]

I have an ampeg SVT vr and pf50t. When our group practices at our practice house, the amps get hot. I’ve been told that’s how tube amps do. They get hot when you play them, at least the chassis anyway. When we play at the church, the back of my SVT is not hot, and I’m playing longer than what we play when we practice. I’ve used the SVT at church twice and neither time has the back been hot. At our practice house even my pf50t was hot when I used it. Any idea of what’s different at church? And at the house two different rooms have been used each time I’ve felt heat

 

[agedhorse]

Yes, tube amps get hot. Higher ambient temperature increases the heat perceived because the temperature rise is more or less a constant, so start warmer will end warmer.

 

[beans-on-toast]

If your playing volumes for each amp are the same at both locations, it comes down to air ventilation and ambient temperature around the amp. If the amp is stuck in a corner or against a wall heat will not dissipate as well.

Pushing an amp harder will generate some additional heat.

 

[Wasnex]

If placement at your house restricts air circulation more, the amps will get hotter.

If the line AC at your house is higher, the amps will run hotter.

The tube cage on the PF50T gets pretty hot (normal IMHO).

An SVT has forced air cooling. No idea how effective it is with the VR, but I would expect warm rather than hot.

 

[Cory rich40]

If placement at your house restricts air circulation more, the amps will get hotter.

If the line AC at your house is higher, the amps will run hotter.

The tube cage on the PF50T gets pretty hot (normal IMHO).

An SVT has forced air cooling. No idea how effective it is with the VR, but I would expect warm rather than hot.

Yeah definitely warm but not super hot

 

[Tim Skaggs]

I have an ampeg SVT vr and pf50t. When our group practices at our practice house, the amps get hot. I’ve been told that’s how tube amps do. They get hot when you play them, at least the chassis anyway. When we play at the church, the back of my SVT is not hot, and I’m playing longer than what we play when we practice. I’ve used the SVT at church twice and neither time has the back been hot. At our practice house even my pf50t was hot when I used it. Any idea of what’s different at church? And at the house two different rooms have been used each time I’ve felt heat

Hmm, an SVT is 300 watts and a PF50 is 50 watts? Are you cranking the PF50 and idling the SVT?

Transistor amps get hot also. If you push a 50 watt solid state amp and idle a 300 watt solid state amp, you will notice a difference in their temperature also.

 

[brianrost]

Check out the AC power requirements for tube amps sometime. I had a 1961 Bassman that was rated 50W RMS but on the back panel next to the fuse it said "117 VAC, 200 watts". That's 150 watts generating heat instead of moving speaker cones.

 

[JFScheck]

Check your tube bias, incorrectly set can make the amp run hotter then needed…

 

[agedhorse]

Check your tube bias, incorrectly set can make the amp run hotter then needed…

Wouldn’t explain why it’s hotter in one location but not the other.

 

[Johnny Fingers]

Why pay attention to the amp heat at all? Turn the unit on, let it warm up and play away. If it’s working that’s good. As long as it isn’t smoking, crapping out or smells funny you’re in business.
If it’s making you too hot point a fan at yourself, don’t worry about the amp. It can handle it.

 

[jimmydean]

Do like me and just have your Roadie hold an electric fan behind your amp . Now what your Roadie does behind your amp with a fan .......I don't want to know .

 

[Cory rich40]

Check out the AC power requirements for tube amps sometime. I had a 1961 Bassman that was rated 50W RMS but on the back panel next to the fuse it said "117 VAC, 200 watts". That's 150 watts generating heat instead of moving speaker cones.

Yeah definitely warm but not super hot

And at the house I have been 2 feet from the wall. At church I have been out in the open kind of, so I think my question has been answered

 

[coy garcia]

I think they sound better when hot so I leave mine on after soundcheck in standby. Indoors, closed off corners, and hot weather makes it hotter and that's ok...nothing to worry about. I have a pf50t and boogie 400 but mostly use the pf.

 

[STRMan]

Hell is hot, so I'm thinking church is cool. I suspect the amplifier temperature differential is due to divine intervention.

 

[gstaats]

I'd imagine the church may have a better/ more active hvac system and is in a much larger room to dissipate heat better. (Depends on lighting too.m hopefully modern cool led lighting is utilized)

 

[Axtman]

Speaking of tubes and heat. Dave, of Dave's World of Fun Stuff, mentioned that he used to bring his SVT into the motel room and drape the blankets over it. That way it heated his bed.

Start the video at 7:00.

 

[Bertr]

Speaking of tubes and heat. Dave, of Dave's World of Fun Stuff, mentioned that he used to bring his SVT into the motel room and drape the blankets over it. That way it heated his bed.

Start the video at 7:00.

Hopefully he'll never decide to heat up his bath.

 

[mike buzzetti]

power = heat in tube's at least

 

[Smith357]

Could something like the main circuit voltage in the building, 110 or 120, affect the load on the transformer in the amp generating more or less heat?

 

[agedhorse]

Could something like the main circuit voltage in the building, 110 or 120, affect the load on the transformer in the amp generating more or less heat?

Not really, slightly but not significantly so.